Dialysis catheter

Abstract

A dialysis catheter comprising a first portion having a first dianeter, an elongated distal portion having a second diameter smaller than the first diameter, and a transition region between the first portion and distal portion. A first longitudinally extending central lumen configured to deliver blood terminates in an opening in the distal portion. At least two independent longitudinally extending lumens are positioned radially of the first lumen, configured to withdraw blood from a patient, and terminate in a longitudinally directed opening in the transition portion.

What is claimed is: 
     
       1. A dialysis catheter comprising:
 a catheter body having a proximal portion, a distal portion, a reduced diameter distal tip, a first longitudinally extending lumen configured to deliver blood to a patient, and a second longitudinally extending lumens configured to withdraw blood from a patient; 
 a first blood delivery opening formed in the distal portion of the catheter body, the blood delivery opening being in fluid communication with the first lumen and configured for passage of blood therethrough; 
 a second blood withdrawal opening formed in the distal portion of the catheter body, the blood withdrawal opening being in fluid communication with the second lumen and configured for passage of blood from a patient, wherein the second opening is positioned proximally of the first opening; 
 a spacer extending from the catheter body to reduce contact of the catheter body with a vessel wall, wherein the spacer has a distal end and a proximal end, the distal end is positioned to terminate proximal of the reduced diameter distal tip of the catheter body and proximal of the first opening; and 
 a stiffening member removably positionable within the catheter; wherein a proximal portion of the stiffening member has a series of threads for mounting the stiffening member to the catheter. 
 
     
     
       2. The catheter of  claim 1 , wherein the proximal end of the spacer terminates distal of the second opening. 
     
     
       3. The dialysis catheter of  claim 1 , wherein the spacer comprises a wire movable from a straightened position to a bowed position. 
     
     
       4. The dialysis catheter of  claim 1 , wherein the spacer comprises a rib formed by a cutout portion in the catheter body. 
     
     
       5. The dialysis catheter of  claim 4 , wherein the spacer comprises a plurality of ribs movable from a retracted position to a bowed position. 
     
     
       6. The dialysis catheter of  claim 1 , wherein the spacer is movable between a first retracted position and a second position extending outwardly from the catheter body. 
     
     
       7. The dialysis catheter of  claim 1 , wherein the blood delivery opening and the blood withdrawal opening are each formed in a sidewall of the catheter body. 
     
     
       8. The dialysis catheter of  claim 1 , wherein the blood delivery lumen terminates in an opening at a distalmost tip of the catheter. 
     
     
       9. The dialysis catheter of  claim 1 , wherein the stiffening member has a lumen to receive a guidewire for over the wire insertion of the catheter. 
     
     
       10. The dialysis catheter of  claim 1 , wherein the blood delivery lumen is positioned centrally within the catheter body and the blood withdrawal opening is positioned radially of the blood delivery lumen. 
     
     
       11. A dialysis catheter comprising:
 a catheter body having a proximal portion, a distal portion, a reduced diameter distal tip, a first longitudinally extending lumen configured to deliver blood to a patient, and a second longitudinally extending lumens configured to withdraw blood from a patient; 
 a first blood delivery opening formed in the distal portion of the catheter body, the blood delivery opening being in fluid communication with the first lumen and configured for passage of blood therethrough; 
 a second blood withdrawal opening formed in the distal portion of the catheter body, the blood withdrawal opening being in fluid communication with the second lumen and configured for passage of blood from a patient, wherein the second opening is positioned proximally of the first opening; 
 a spacer extending from the catheter body to reduce contact of the catheter body with a vessel wall, wherein the spacer has a distal end and a proximal end, the distal end is positioned to terminate proximal of the reduced diameter distal tip of the catheter body and proximal of the first opening; and 
 a stiffening member removably positionable within the catheter, wherein the stiffening member stretches the body and moves the spacer to a straightened position for insertion. 
 
     
     
       12. A dialysis catheter comprising:
 a catheter body having a proximal portion, a distal portion, a reduced diameter distal tip, a first longitudinally extending lumen configured to deliver blood to a patient, and a second longitudinally extending lumens configured to withdraw blood from a patient; 
 a first blood delivery opening formed in the distal portion of the catheter body, the blood delivery opening being in fluid communication with the first lumen and configured for passage of blood therethrough; 
 a second blood withdrawal opening formed in the distal portion of the catheter body, the blood withdrawal opening being in fluid communication with the second lumen and configured for passage of blood from a patient, wherein the second opening is positioned proximally of the first opening; 
 a spacer extending from the catheter body to reduce contact of the catheter body with a vessel wall, wherein the spacer has a distal end and a proximal end, the distal end is positioned to terminate proximal of the reduced diameter distal tip of the catheter body and proximal of the first opening; and 
 a stiffening member removably positionable within the catheter, wherein the distal tip portion of the catheter includes a shoulder adapted to abut the stiffening member inserted through the first lumen.